So any child born in this game is automatically 18? I've never had a kid in the game so I don't know.
They do exist, but don't appear in-game ti'll they're 18.
If you're curious, just check the saves, which is basically a list of every NPC. Child is almost at the bottom (all important NPCs are there, like family, relationships, your PC, etc).
Look at their stat list, and again, near the bottom, there's a stat called "age". It should look like "1.2648" which means the child is 1YO and something (that something is basically what you raise with the "chilcare" action. Yes, it takes a lot of time). You can easily edit it, but is better to set it to 17.xxx (so it completes aging "normally" in-game to avoid any problems) rather to set it straight to 18.
Personally, what I do is set ages at different states. For example, having onegrow normally (unedited), then have others in different ages, like 5-6, 8-12, 15-17. This means you'll trigger most scenes without having to wait. (there's actually a good amount of scenes as kids grow, ranging from simple events as they learn to talk, to getting them to school and find new contacts -other kids parents-, getting a baby-sitter, or parties as they're older)
learned never to underestimate the lengths some people will go to when they're pursuing something they're passionate about
True, but in this case is WAY too much work.
You'll need to re-do every single animation since a different size model doesn't works properly.
You can actually change a NPC size, but it won't match the animations, so it's pointless.
As for NPC cloths, they will wear whatever they want, based on personality &/or location, regardless of what is in inventory. Only way to force a character to wear specific cloth, or not, is in scene that command them to dress/undress related to scene.
This, basically.
If a character has high fitness for example, it will pick sporty clothes over all; High perversion, sluttier clothes, and so.
I think you could narrow it down by deletingclothes they have, but you need to be careful and give them sets of clothes they'll need for different situations (i.e a formal set of clothes, a working set of clothes, a sports set of clothes, etc).
